1. Field of the Invention
The present invention relates to a flooring material and in particular, to a flooring material mainly consisting of cork, and a flooring method.
2. Description of the Prior Art
A flooring material is one of the most important factors for creating a comfortable dwelling space not only in an individual house but also in a multiple dwelling house. Conventionally, various flooring materials and various flooring methods have been employed. Flooring materials are required to have various superior functions such as in safety in case of fall down, sound shielding/absorption, easiness of walking and caster-running, restoring ability, prevention of fire spreading, heat insulation characteristic, water-proof and chemicals-proof characteristics as well as insect-proof and mildew proof characteristics. The safety in case of fall down means a function to mitigate a shock applied when something falls down, preventing from a disaster, as well as to reduce the injury degree when a person falls down. This safety in case of fall down has become particularly important in the era when the number of aged people is increasing.
The sound shielding. absorption characteristic means a function to reduce a sound volume at a down floor below located below a sound source and absorb a sound reflected within a room. The sound shielding/absorption characteristic also is an important requirement not to cause a noise trouble, especially between neighboring apartments in a multiple dwelling house. The easiness of walking means a function to satisfy an overall evaluation such as not to cause a fatigue feeling and give an appropriate temperature feeling and smoothness or sliding feeling. The easiness of caster running is an evaluation function which evaluates smoothness when moving an object in a room such as a wheel chair and a bed having casters which are more and more often used for an aged person in a house.
The restoring ability means an ability to restore to an initial state after a heavy object is removed, or a restoring ability of a convex formed when a heavy object is fallen down. The fire spread prevention means a function that the material itself is hard to burn. The heat insulation means a heat insulation function or heat maintenance function which increases the cooling and warming effects, suppressing energy consumption. The water and chemical resistance mean that water cannot easily penetrate the flooring material which is not easily affected by chemicals. Furthermore, insect and mildew resistance means a function that reduces living of vermin such as termites and reduces condensation.
Conventionally, tatami (straw mattress) and carpets have been used as the flooring material and there can also be seen popularity of wooden flooring among younger generations. Table 1 below shows the function characteristics of the flooring material according to the present invention in comparison to the tatami, carpet, and the wooden flooring.
TABLE 1 Floor Material according Conven- to the tional present Functions Tatami Carpet Flooring invention Safety in Excellent Good Bad Excellent case of fall down Sound Good Good Bad Good Shielding and absorption Walking Good Good Allowable Good feeling Caster Bad Bad Excellent Good running Restoring Allowable Good Good Allowable ability Fire Bad Bad Bad Excellent spread prevention Heat Excellent Good Bad Excellent insulation Water- Bad Bad Allowable Good proof, chemicals- proof Insect- Bad Bad Good Good proof, Mildew- proof
As is clear from the table above, for example, the tatami shows superior characteristics in safety and heat insulation but has a problem for caster running, fire spread prevention, water and chemical resistance as well as insect-resistance and mildew resistance. Moreover, the carpet has a problem in caster running, fire spread prevention, water and chemical resistance and in insect and mildew resistance. Furthermore, the wooden flooring, although showing a superior characteristic in caster running, restoring ability and insect and mildew resistance, has problems in the other aspects. Thus, the tatami and the carpet or the wooden flooring which have been widely used cannot be evaluated as ideal flooring materials.
In a multiple dwelling house, sound shielding and absorption are quite important between upper and lower floors. In order to obtain a sufficient sound shielding characteristic, it is necessary to use a concrete slab having a sufficient thickness. For example, even when a high-efficiency wooden flooring is employed, the slab thickness should be at least 180 mm or above in order to obtain the necessary sound shielding class L.sub.H (Heavy load shock sound shielding class)=50 and L.sub.L (Light load shock sound shielding class)=50.
A multiple dwelling house using such thick concrete slabs require more building materials such as concrete and reinforcing steel and as a result, requires more building materials to sustain strength when the entire weight is increased. Consequently, there is a problem that a multiple dwelling house increases building costs and a period of time required for building. Moreover, as the concrete slab increases its thickness, a ceiling height in a room is more limited.
Conventionally, the main building material has been wood, but nowadays when protection of the woods resource has become one of the ecology slogans, it is necessary to develop a new material which suppresses woods destruction. The applicant of the present invention has examined various materials in search of an ideal flooring material, paid attention to a cork material made from a cork oak tree which can be supplied at a stable rate without destroying woods, and developed a product from the cork which satisfies the aforementioned flooring material conditions.
The cork material which is porous and light in weight, and has elasticity, non-penetration characteristic, and low thermal conductivity, is widely known as a cork stopper of a wine bottle and has various applications in various fields. As a building material, the cork exhibits a warm wooden feeling as an interior design product and superior characteristics in sound shielding and thermal insulation. Consequently, the cork is employed not only as an interior product but also as an adjusting material of expansion and contraction of a concrete building, a friction reducing material, a vibration suppressing material, and the like.
However, the cork material is scarcely used in a main portion of a building such as a wall and a floor but normally used as the aforementioned auxiliary building materials or a decorative as a part of a wall. This is because the cork tiles are comparatively expensive; it is difficult to accurately align the cork tiles; and there is an incorrect recognition that the cork is mechanically weak and is easily broken as can be seen in a cork stopper of a bottle or the cork has low water-resistance.